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Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
...able of a class with the mutable keyword. As far as I can see it simply allows you to modify a variable in a const method:
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How to get the current time in Python
...gt; from datetime import datetime
Then remove the leading datetime. from all of the above.
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Transpose/Unzip Function (inverse of zip)?
...'d', 4)])
[('a', 'b', 'c', 'd'), (1, 2, 3, 4)]
The way this works is by calling zip with the arguments:
zip(('a', 1), ('b', 2), ('c', 3), ('d', 4))
… except the arguments are passed to zip directly (after being converted to a tuple), so there's no need to worry about the number of arguments g...
How do HashTables deal with collisions?
...lookups in hash tables very slow.
Option 2: If the hash table entries are all full then the hash table can increase the number of buckets that it has and then redistribute all the elements in the table. The hash function returns an integer and the hash table has to take the result of the hash funct...
Best way to create an empty object in JSON with PHP?
To create an empty JSON object I do usually use:
7 Answers
7
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How to create a .NET DateTime from ISO 8601 format
...standard, they seem to be able to parse only a limited subset of it. Especially it is a problem if the string contains time zone specification. (Neither it does for basic ISO8601 formats, or reduced precision formats - however this is not exactly your case.) That is why I make use of custom format s...
How do I profile memory usage in Python?
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This one has been answered already here: Python memory profiler
Basically you do something like that (cited from Guppy-PE):
>>> from guppy import hpy; h=hpy()
>>> h.heap()
Partition of a set of 48477 objects. Total size = 3265516 bytes.
Index Count % Size % Cumulat...
Javascript when to use prototypes
...ods, over and over.
Instead, those methods are defined on a prototype and all jQuery objects "inherit" that prototype so as to gain all those methods at very little runtime cost.
One vitally important part of how jQuery gets it right is that this is hidden from the programmer. It's treated purely ...
Is the order guaranteed for the return of keys and values from a LinkedHashMap object?
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The Map interface provides three
collection views, which allow a map's contents to be viewed as a set
of keys, collection of values, or set
of key-value mappings. The order of
a map is defined as the order in which
the iterators on the map's collection
views return their ...
Python argparse: How to insert newline in the help text?
...nfortunately Only the name of this class is considered a public API. All the methods provided by the class are considered an implementation detail. So probably not a great idea, although it might not matter, since 2.7 is meant to be the last 2.x python and you'll be expected to refactor lots ...